The objective of this project is to test the effectiveness in man of S-2-(3 aminopropylamino) ethylphosphorothioic acid (WR-2721), a protector against ionizing radiation in the normal tissues of the mouse. This drug also has been shown to protect the normal tissues of mice against alkylating agents, such as cis-Platinum and cyclophosphamide. WR-2721 rapidly (within 15-20 minutes) and actively concentrates in all normal tissues in mice except for brain and spinal cord. However, multiple mouse tumor tests for incorporation show concentrations that approach, but do not exceed, serum levels within approximately 1.5 hours. Phase I studies of single doses of drug plus radiation therapy have attained a level of 450 mg/M2 without significant toxicity. Levels of 600 and 740 mg/M2 will be tested. Low level drug plus four radiation fractions per week for three weeks have been successfully tolerated. These studies will be carried to the highest drug level tolerated with up to five radiation fractions in three and seven weeks. In selected patients, pharmacologic studies using 14C-labelled drug will determine serum levels and clearance versus normal and tumor tissue incorporation at the beginning and end of multiple doses. Similarly, the maximum tolerated dose of drug with cis-Platinum and cyclophosphamide will be discerned. Phase II studies to obtain the dose reduction factor for multiple doses of radiation and the increased tolerance for the alkylating agents will be completed. These will lead to Phase III trials observing normal tissue protection and tumor response.